Shit man! A 4 second postive and 4 second negative on the leg press to failure would be more than enough for me. I seriously doubt that I would even be able to do a bodyweight squat after that torture session lol
No four second positive.....I just do a standard explosive type push. I used 630lbs on the icarian leg press, then only 90lbs/side on one of those squat machines. Leg press sets were 8,8,8.....the squat machine was 19, 15, and 12 (followed by some nice near vomitting)